y uttered, while his
_twee_, or _tuwee_, is quite in the voice and manner of the wood pewee's
clear, plaintive whistle; usually a monosyllable, but at other times
almost or quite dissyllabic. The olive-sided, on the other hand,
imitates nobody; or, if he does, it must be some bird with which I have
yet to make acquaintance. _Que-que-o_ he vociferates, with a strong
emphasis and drawl upon the middle syllable. This is his song, or what
answers to a song, but I have seen him when he would do nothing but
repeat incessantly a quick trisyllabic call, _whit, whit, whit_;
corresponding, I suppose, to the well-known _whit_ with which the
phoebe sometimes busies himself in a similar manner.

Of more interest than any flycatcher--of more interest even than the
Tennessee warbler--was a bird found by the roadside in the village,
after we had been for several days in the place. Three of us were
walking together, talking by the way, when all at once we halted, as by
a common impulse, at the sound of a vireo song; a red-eye's song, as it
seemed, with the faintest touch of something unfamiliar about it. The
singer was in a small butternut-tree close upon the sidewalk, and at
once afforded us perfectly satisfactory observations, perching on a low
limb within fifteen feet of our eyes, and singing again and again, while
we scrutinized every feather through our glasses. As one of my
companions said, it was like having the bird in your hand. There was no
room for a question as to its identity. At last we had before us the
rare and long-desired Philadelphia greenlet. As its song is little
known, I here transcribe my notes about it, made at two different times,
between which there appears to have been some discussion among us as to
just how it should be characterized:--

"The song is very pretty, and is curiously compounded of the red-eye's
and the solitary's, both as to phrase and quality. The measures are all
brief; with fewer syllables, that is to say, than the red-eye commonly
uses. Some of them are exactly like the red-eye's, while others have
the peculiar sweet upward inflection of the solitary's. To hear some of
the measures, you would pass the bird for a red-eye; to hear others of
them, you might pass him for a solitary. At the same time, he has not
the most highly characteristic of the solitary's phrases. His voice is
less sharp and his accent less emphatic than the red-eye's, and, so far
as we heard, he observes decidedly longer re